Two
versions available to support either ISA or PCI motherboard machines

General
Purpose Serial Interface (GPSI) for use with AD95x-II Analyzer and AD991 MPEG
Signal Source

SMPTE 310M Synchronous Serial Interface

ECL
Serial DC and AC

DHEI

RS422/RS485

Synchronous Serial
Interface

Two versions available to support either ISA or PCI motherboard
machines

ASI

Designed
for product developers, program providers and broadcasters AD95x-II and AD991
have the ability to interface to MPEG-2 compressed digital video data streams
directly from high-speed serial interfaces.

Functionality

The
ASI adapter consists of a daughter card PCB for the AD95x-II and AD991 main
MPEG processing card.

The ASI contains the processing electronics to
allow a digital video transport stream to be fed at baseband directly to the
MPEG processing system.

An ASI interconnect physically consists of
two nodes: a transmitting node and a receiving node. This unidirectional copper
coaxial cable carrying data from the transmitting node to the receiving node
is referred to as a link. The link is used by the interconnected ports to
perform communication. It is a point-to-point link system. Physical equipment
such as video or audio compressors, multiplexers, modulators, etc., can be
interconnected through these links. The PCI version of this card has the capability
to timestamp packets as they arrive at the interface. This can then be used
for offline analysis of PCR timing characteristics such as PCR overall jitter,
PCR frequency offset and PCR drift rate when used in the AD95x-II family of
MPEG Test Systems.

Configuration

Once the ASI adapter is fitted,
the AD95x-II will automatically detect the card on power-up. The Asynchronous
Serial Interface settings may then be configured from both the Player and
Monitor/Recorder programs.

The clock can be set to calculate the playout
clock rate from the PCR Fields in the playout file or the clock rate to be
entered directly as either the Bit Rate or Byte Rate frequency.

The
ASI Adapter Has Four Optional Mode Settings:

ASI -
The operating mode of the standard ASI

ASI Burst - Data is
transmitted in bursts of 1, 2, 3 or 4 transport stream packets. The number
of packets in each burst is specified in the Packets field

ASI
Forced Error - Causes an error byte to be transmitted in position 15
of each packet

M2S - Selects Divicom M2S compatible mode

Self-test

This
adapter card has a Built-in Self Test (BIST) function that can be used to
troubleshoot the ASI interface and any connected serial link components.

It
can be set to generate a special Pseudo Random Binary Stream (PRBS) test sequence
and report the error rate detected.

GPSI Interface Card.

GPSI

Designed
for product developers, program providers and broadcasters, the AD95x-II and
AD991 now have the ability to interface to MPEG-2 compressed digital video
data streams directly from high-speed serial interfaces.

This greatly
simplifies interconnection to digital video systems and allows direct interconnection
with third party equipment via Tektronix' General Purpose Serial Interface
(GPSI).

Functionality

The GPSI consists of a daughter card
PCB for the AD991, AD95x-II, and AD991 main MPEG processing card. The GPSI
contains the processing electronics to allow a digital video transport stream
to be fed at baseband directly to the MPEG processing system. It is able to
internally recover or generate the clock signal on bi-phase interfaces with
on-board PLL and LSI logic. High precision clock references support 8-VSB
and 16-VSB bit rates.

Configuration

The GPSI is selected via
the AD95x-II and AD991 user interface with the facility to select various
clock sources, bit rates and other settings.

L-Band Interface Card.

L-Band

Designed
for product developers, program providers and broadcasters, the AD95x-II now
has the ability to monitor, record and analyze DVB and ATSC data streams directly
from the RF L-Band.

This greatly simplifies interconnection of ATSC/DVB/MPEG
systems and allows off air monitoring direct from satellite feeds and before
upconversion at transmission stations.

Functionality

The L-Band
interface consists of a daughter card PCB for the AD95x-II main MPEG processing
card. The L-Band interface contains a QPSK demodulator and the processing
electronics to allow an MPEG transport stream to be fed at baseband directly
to the AD95x-II DVB/MPEG processing system.

Configuration

The
user inputs a set of parameters: Satellite frequency; LO frequency; symbol
rate; Viterbi ratio; DC power/Polarization (off/13 V/18 V); 22 kHz tone switching.
A set of preconfigured channels can be stored allowing the user to switch
conveniently between them.

Bit Error Measurement

Characteristics

ASI

The
Asynchronous Serial Interface (ASI) adapter allows connection to equipment
with an interface compliant with the DVB Asynchronous Serial Interface as
defined in DVB document A010 (Interfaces for CATV/SMATV Headends and Similar
professional equipment).

The ASI also allows connection to equipment
with the Divicom M2S interface and provides burst mode packet transmission.

ASI
uses a fixed rate data stream operating at 270 Mb/s. The ASI adapter allows
either playout, monitoring or recording of transport streams. Simultaneous
playout and recording are not possible. When recording or monitoring, the
incoming data is looped through to the ASI output.

Connectors and Cables - High quality 75 Ω BNC connectors
and double shielded cable should be used to give a practical operating range
of several hundred meters.

Note: To meet system EMC/CE emission
regulations the ASI BNC connector screens have to be electrically connected
to the AD95x-II chassis. The ASI cable must therefore not be directly connected
to equipment with a potentially different chassis voltage such as apparatus
in a different building or to apparatus connected to an electrical supply
originating from a different phase.

The applicable EMC specs are detailed
in the AD95x-II data sheet.

GPSI

The GPSI receives 188,
204 and 208 byte transport stream packet formats and strips off the FEC to
leave 188 bytes for use by AD95x-II and AD991. It transmits inserting dummy
Reed Solomon (204 bytes or 208 bytes). SSI & SMPTE 310M can recover clock
and data in the range 1 to 44 MHz.

ATSC

Transmit bit rates from 1 Mb/s to 44 Mb/s are supported with
special high precision support for the ATSC 8-VSB (19,392,658.46 Mb/s) and
16-VSB rates (38,785,316.92 Mb/s).

AD95x-II - Receive
bit rates from 1 Mb/s up to 44 Mb/s with automatic clock recovery are supported
with special support for ATSC 8-VSB (19.392,658.46 Mb/s). Higher receive rates
up to 44 Mb/s can be achieved using an additional external clock input.

Transmit and
receive bit rates from 1 Mb/s up to 50 Mb/s are supported with special high
precision support for the ATSC 8-VSB (19,392,658.46 Mb/s) and 16-VSB rates
(38,785,316.92 Mb/s), also provided is psync bit at the first bit position
for each packet.

DHEI - (Digital Headend Expansion Interface)
- This is a General Instrument proprietary interface. It is a serial,
differential ECL interface that has gapped packet clock, data and sync.

Transmit bit rates from 1 Mb/s to 44 Mb/s are supported
with special high precision support for the ATSC 8-VSB (19,392,658.46 Mb/s)
and 16-VSB rates (38,785,316.92 Mb/s).

Receive bit rates from 1 Mb/s
up to 44 Mb/s are supported with automatic clock recovery.

Other
Features - Input and output signal configuration is fully flexible and
under software control.The GPSI card is a single channel card, but the input
signal loops through to the output on the same card.

The GPSI card can be
customized to receive and transmit higher data rates to suit a wide range
of applications.

L-Band

DVB Specification - DVB-S
to EN 300 421.

Demodulation - QPSK.

Input Impedance
- 75 Ω nominal.

Reverse Loss Ratio (RLR) - Better than
-7 dB (-10 dB typical).

Input Connector - F Type.

Input
Level Range for Full Performance - -60 to -30 dBm.

Maximum
Operational Input Level - -20 dBm.

Maximum DC Level at Input
- +25 V.

Minimum Input Frequency - 950 MHz.

Maximum
Input Frequency - 2150 MHz.

Tuning Increment - 125 kHz.

Carrier
Acquisition Range - ±10% of symbol rate.

Minimum Symbol Rate
- 1 Msymbol/s.

Maximum Symbol Rate - 45 Msymbol/s.

Symbol
Rate Increment - 1 ksymbol/s.

Symbol Rate Acquisition Range
- ±240 ppm from nominal value.

Irreducible BER - Better
than 1 x10-6 before FEC.

Viterbi Rates - 1/2, 2/3,
3/4, 5/6, 7/8 programmable.

Spectral Inversion - Automatic
support.

Reed Solomon - DVB-S standard (204, 188, T=8).

LNB
DC Power Supply - 0 V, +13 V or +18 V (±1 volt).

Tone Switching
- 22 kHz ±20%.

Loop-through Output Level - Input level
±3 dB.

Loop-through Output Impedance - 75 Ω nominal.

Loop-through
Connector - F Type.

Note: At low symbol rates care is needed
to ensure that the carrier frequency and symbol rate configured by the user
accurately match the actual (rather than nominal) values of these parameters
subject to the acquisition tolerances mentioned above.